1. Field of the Invention
The present invention relates to a display device for use in displaying characters and background images in a video game program and video game device, and more particularly, to an image display which is effectively operable in cases where a character is moving between scenes having mutually different backgrounds.
2. Description of the Related Art
With increases in hardware processing capacity, there has been a steady improvement in image quality in all game software over recent years. In general, improved image quality signifies an increase in the quantity of image data. This means that a waiting time tends to become long during transferring data from an external storage device to a memory.
A waiting time of this type does not practically cause any serious problem to occur in some sorts of games, such as a chess game, a strategic simulation game, executed in accordance with video game programs. This is because real-time manipulation of a player is not directly concerned with results of such games, although absence of any waiting time is ideal in such games also. In other words, such a waiting time adversely and significantly does not affect the result of such games.
In contrast to these games, in games, such as action games, the realtime reactions of the player have a significant effect on the result of the game. In consequence, any waiting time seriously and directly influences a result of the game because the rhythm of the player's input operations is turbulent due to the waiting time. This may cause significant stress to the player.
In particular, many of the typical domestic video game devices of recent years use an optical disk, such as a CD-ROM, as a storage medium. However, such optical disks have a slow data reading speed as compared to other external storage devices, such as a fixed magnetic disk device, or the like. Such optical disks are therefore particularly susceptible to the problem described above.
Herein, consideration is made about a case where the background changes due to the fact that a character has moved from in front of the current background to an adjacent background. Then if it is supposed that all of the backgrounds in the directions to which the character could possibly move have been previously read in from an external storage device, the aforementioned waiting time will not arise, whatever direction the character moves in.
However, if high-quality background images are being used, as in current games, then the amount of background image data will inevitably increase, and it therefore becomes impossible to transfer all of the adjacent background images previously into a limited RAM space. Consequently, if the character is about to move forwards from the end region of a screen, it is necessary to switch between background images, and this requires the external storage device to be accessed.